An articular-sided tear of the rotator cuff is an injury affecting the shoulder. This condition involves a partial tear on the joint-facing surface of one of the rotator cuff tendons. It is an incomplete disruption of tendon fibers, unlike full-thickness tears. This injury can impact shoulder function and cause discomfort.
Understanding the Shoulder and Rotator Cuff
The shoulder is a complex ball-and-socket joint, allowing a wide range of motion. A group of four muscles and their tendons, collectively known as the rotator cuff, stabilize this joint. These muscles include the supraspinatus, infraspinatus, teres minor, and subscapularis. Their tendons blend together and attach to the upper arm bone, the humerus, forming a protective cuff around the shoulder joint.
The rotator cuff helps lift and rotate the arm, keeping the humerus centered within the shoulder socket. The “articular side” of a rotator cuff tendon is the surface that faces the inside of the shoulder joint capsule and the cartilage of the humeral head.
What Defines an Articular-Sided Tear
An articular-sided tear is a partial-thickness rotator cuff tear on the joint-facing surface of a tendon. Unlike a full-thickness tear where the tendon is completely separated, an articular-sided tear means some tendon fibers remain intact. This tear is distinct from a bursal-sided tear, which affects the outer surface of the tendon closer to the bursa, a fluid-filled sac that reduces friction. Articular-sided tears are two to three times more frequent than bursal-sided tears.
These tears commonly affect the supraspinatus tendon, which is located at the top of the shoulder. The tear often appears as a linear fluid signal defect on imaging, typically near where the tendon inserts into the humerus. In some instances, it can involve a delamination of tendon fibers, meaning layers of the tendon separate. Occasionally, these tears are classified with specific terms like PASTA lesions, which denote a partial articular supraspinatus tendon avulsion.
How These Tears Develop
The development of articular-sided rotator cuff tears is often multifactorial, involving both sudden events and gradual wear. Acute injuries, such as a fall onto the shoulder or a sudden, forceful jerk, can cause these tears. Many tears also develop over time due to repetitive stress and degenerative changes. Activities involving overhead arm movements, common in athletes and certain occupations, contribute to repetitive microtrauma that can injure the tendons.
Age-related changes also play a role, as tendons can weaken and degenerate. The articular side of the rotator cuff tendon, particularly the supraspinatus, has a relatively poorer blood supply (hypovascularity). This reduced blood flow can hinder the tendon’s ability to repair itself and make it more susceptible to tearing. Factors like glenohumeral joint instability and internal impingement, where the humeral head contacts the labrum and cuff during specific arm positions, can also contribute to these tears.
Recognizing the Signs and Getting a Diagnosis
Symptoms of an articular-sided rotator cuff tear can impact daily life. Pain is a common complaint, often described as a dull ache deep within the shoulder. This pain may worsen at night, especially when lying on the affected side, and can interfere with sleep. Movements involving lifting the arm overhead or reaching behind the back often intensify the discomfort.
Other signs include weakness when lifting or rotating the arm, and sometimes a clicking or popping sensation during certain shoulder movements. Diagnosis typically begins with a physical examination, assessing the shoulder’s range of motion, strength, and tenderness. Imaging studies are also important. Magnetic Resonance Imaging (MRI) is a preferred method for visualizing soft tissue injuries like rotator cuff tears, showing fluid signal defects on the articular surface of the tendon to confirm the tear’s presence and location.
Approaches to Healing
Healing an articular-sided rotator cuff tear often begins with conservative management. Rest, applying ice to the affected area, and taking anti-inflammatory medications are common initial steps to reduce pain and swelling. Physical therapy focuses on exercises to restore shoulder mobility, strengthen surrounding muscles, and improve shoulder mechanics. In some cases, injections, such as cortisone, may manage pain and inflammation.
If conservative treatments do not relieve symptoms after several months, or if the tear is significant, surgical options may be considered. Arthroscopic repair is a common surgical approach. During this procedure, a surgeon uses small incisions and a camera to visualize the joint and repair the torn tendon, often reattaching it to the bone. The goal of treatment is to alleviate pain, restore functional movement, and improve shoulder strength.